[Epidemiological characteristics and trends of bone mass gain in physical activity intervention trials for children...

High-impact or weight-bearing physical activities have positive effects on bone mass gain in children and adolescents from the findings of the physical activity intervention trials for them. These physical activity trials have been relatively short term in research design and some of the intervention trials had small numbers of subjects. Significant benefits on bone mass gain in children and adolescents were observed in almost all studies concerning physical activity intervention trials, although there was considerable variability in magnitude. The discrepancies in findings might relate to the characteristics of participants (sex, age, maturity); the characteristics of the intervention (intensity, frequency, duration); and the bone region assessed (cortical vs. trabecular). In current research on bone mass gain in children and adolescents, there is a lack of data about the effects of different types of physical activity, the long-term effects of physical activity during growth, and the interaction between pubertal development and physical activity. The results of this study call for a further accumulation of evidence about the effects of physical activity to promote bone health in children and adolescents.